The first challenge in this project was the high standard of purification, as the wastewater was to be suitable for direct discharge into a receiving water body. The effluent values should therefore be below the following values: COD 100 mg/l, BOD₅ 25 mg/l and filterable substances 75 mg/l. The second challenge was the limited space on the company premises. Therefore, the wastewater treatment plant had to be particularly compact.

To meet all customer requirements best, the ClearFox® team opted for an SBR system in tanks. These are rotationally moulded and therefore have no predetermined breaking point. This makes them particularly stable, durable, and suitable for both above-ground and below-ground installation.

The ClearFox® team assembled the treatment plant from a total of seven tanks. At the beginning, the wastewater flows through a drum filter to separate the first coarse solids from the wastewater. The first three tanks serve as buffer storage to compensate for the irregular wastewater load. From there, the plant pumps the wastewater into two more tanks in which the SBR system is installed. This is where the biological treatment takes place. The powerful aeration system supplies the wastewater with oxygen and thus ensures the growth of microorganisms.

The sludge produced in the process is stored in the two remaining tanks. As the entire treatment plant works very efficiently, the sludge largely decomposes by itself, which is why the sludge only needs to be removed once a year. For this project, the ClearFox® team took over the complete project planning, the construction of the tank system, the installation and commissioning on site as well as the training of the employees.